Wang Zhilue, Qu Shoujiang, Xiang Hongping, He Zhangzhen, Shen Jun
School of Materials Science and Engineering, Tongji University, 4800 Caoan Road, Shanghai 201804, China.
State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou 350002, China.
Materials (Basel). 2020 Apr 11;13(8):1805. doi: 10.3390/ma13081805.
The stability, physical properties, and electronic structures of Cr(NCN) were studied using density functional theory with explicit electronic correlation (GGA+). The calculated results indicate that Cr(NCN) is a ferromagnetic and half-metal, both thermodynamically and elastically stable. A comparative study on the electronic structures of Cr(NCN) and CrO shows that the Cr atoms in both compounds are in one crystallographically equivalent site, with an ideal 4+ valence state. In CrO, the Cr atoms at the corner and center sites have different magnetic moments and orbital occupancies, moreover, there is a large difference between the intra- (12.1 meV) and inter-chain (31.2 meV) magnetic couplings, which is significantly weakened by C atoms in Cr(NCN).
利用含显式电子关联的密度泛函理论（GGA+）研究了Cr(NCN)的稳定性、物理性质和电子结构。计算结果表明，Cr(NCN)是一种铁磁半金属，在热力学和弹性方面均稳定。对Cr(NCN)和CrO的电子结构进行的对比研究表明，两种化合物中的Cr原子处于一个晶体学等价位置，具有理想的4+价态。在CrO中，位于角部和中心位置的Cr原子具有不同的磁矩和轨道占据情况，此外，链内（12.1毫电子伏特）和链间（31.2毫电子伏特）磁耦合之间存在很大差异，而在Cr(NCN)中这种差异被C原子显著削弱。
